The present invention relates in general to electric power conditioning and distribution in electric vehicles, and, more specifically, to an integrated electric power module combining the functionality of DC-to-DC converters, AC inverters, and traction motor inverters for use in hybrid and fuel cell passenger vehicles.
The use of transportation vehicles (e.g., automobiles) using electric traction drives is increasing. Hybrid vehicles combining electric traction drives with internal combustion engines and pure electric vehicles offer potential improvements in fuel efficiency and reductions in gaseous and particulate emissions. A high voltage (e.g., about 300 volt) source typically comprising a battery is charged by a generator (such as a fuel cell or a dynamoelectric generator driven by the combustion engine) and the high voltage from the battery is distributed and conditioned by various converter and inverter modules for use by different vehicle systems. Power inverter modules produce multiphase AC power for driving the front and rear traction motors. Separate DC-to-DC converters are usually provided for down-converting the high voltage to a 42V bus and to a 14V bus for supplying most of the other electrical loads. A single-phase DC-to-AC inverter may also be provided for creating 120V and/or 240V AC power for operating electrical accessories via a plug-in outlet.
One obstacle to widespread adoption of such vehicles has been the high cost of the relatively numerous and complex components that have been required. Thus, it would be desirable to reduce the component costs associated with electric power conditioning and distribution in hybrid and electric vehicles. Reduction of the gross weight of these components is also desirable since any further efficiency improvements make the vehicles even more attractive compared to conventional gasoline vehicles.